MEXICO CITY — Mexico has done little over the past decade to improve the squalid living conditions of mentally disabled adults and children who are in institutions, an international advocacy group charged Tuesday.

Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

Patients are tied to wheelchairs, walls of shelters and institutions are stained with feces and pools of urine cover the floor, and children and adults often scream in agony and confusion. the Washington-based Disability Rights said.

Its report added that some patients have even disappeared.

The group visited 20 shelters, orphanages and mental health facilities over the past year to follow up on an investigation it conducted 10 years ago that exposed widespread abuse and inefficiency in Mexico's system of caring for its mentally disabled.

Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

The first report provoked outrage and the government promised to make changes.

A decade later, little has been done, said the report compiled with the help of the Mexican Commission for the Defense and Promotion of Human Rights. The two groups visited private and public institutions that allowed them access in Mexico City as well as the states of Mexico, Jalisco, Oaxaca, Puebla and Veracruz.

Institutions still have little government oversight, the report said. Some patients have disappeared from the system because of shoddy record-keeping as they were transferred from one facility to another.

A Mexico City woman described her struggle to track down her granddaughter, who was 6 years old when local authorities claimed she was being abused at home and needed to be placed in foster care in 2005.

"What can I do? The authorities don't want, can't or don't have an explanation for me," Ardelia Martinez Estrada said in Spanish at a news conference.

She was finally granted custody of her granddaughter, Ilse Michelle Curiel Martinez, in 2007 and maintains that her granddaughter was not abused.

Eric Rosenthal, the director of Disability Rights International, said researchers asked the Mexican government how many people were in institutions and how many might be unaccounted for but they were given no figures.

"I would encourage you to ask the government that question because we did and we did not get answers," he said.

The report said that at one facility for girls, the staff did not know the names, ages or the reasons why some of the patients where there. In another case, researchers found two women who grew up at an institution who are now working there without pay. No record of their internment exists, according to the report.

Some patients are held indefinitely because they don't have relatives to claim them or their families can't find them, Rosenthal said.

Mexico is one of the many countries that ratified the United Nations Convention on the Rights of Persons with Disabilities in 2006 and will now have to respond to the allegations in the report, Rosenthal said.

A spokesman for Mexico's Health Department did not immediately return a call for comment.

The groups are calling for a moratorium on the institutionalization of children and say more mental health funding is necessary to treat people in their communities instead of sending them to facilities.

The groups showed a video of a clinic where patients walked around nude and rolled around in their own urine. Some walked back and forth aimlessly and others poked their eyes and bit their fingers and their hands.

Rosenthal said part of the problem is that Mexico's system to care for the disabled is decentralized and it is sometimes unclear who is responsible for ensuring that people are treated humanely.

One facility acknowledged it had lobotomized four patients in the last four years, the report said.

"It is as if time has stood still at these institutions," Rosenthal said, noting that some of the patients he met at some of the worst facilities a decade ago are still there, suffering the same abuse.

The report tells of a man and a woman tied to wheelchairs 10 years ago who are still receiving the same treatment.

"I can tell you that the sounds of the people screaming and children in the institutions still haunt me after a year of visiting countless institutions and seeing hundreds and hundreds of people whose lives have been thrown away living in these atrocious conditions," he said.

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